Here's a brief history of the folks other than Clinton who have made some kind of comparison between Putin/Russia and Hitler/Nazi Germany:
Sen. Lindsey Graham (R-S.C.): "If you could go back in time, would you have allowed Adolf Hitler to host the Olympics in Germany? To have the propaganda coup of inviting the world into Nazi Germany and putting on a false front?"
Former national security adviser Zbigniew Brzezisnki (in 2008): Putin is "following a course that is horrifyingly similar to that taken by Stalin and Hitler in the 1930s."
And again today: Called Putin "a partially comical imitation of (former Italian Prime Minister Benito) Mussolini and a more menacing reminder of Hitler."
Canadian Foreign Affairs Minister John Baird: "The Sudetenland had a majority of Germans. That gave Germany no right to do this in the late 1930s."
Canadian Prime Minister Stephen Harper: "We haven't seen this kind of behavior since the Second World War."
Anti-Putin activist and former chess champion Garry Kasparov: "Intentionally or not, the Putin regime has followed the Berlin 1936 playbook quite closely for Sochi."
Russian historian Andrey Zubov: "This has all happened before. Austria. Early March, 1938. The Nazis want to build up their Reich at the expense of another state."
British actor and gay rights activist Stephen Fry: "He is making scapegoats of gay people, just as Hitler did Jews. He cannot be allowed to get away with it."
International security expert Jonathan Eyal: "The Sudetenland option is not his first priority, but it is his fail safe priority."
Russian satirist Viktor Shenderovich: In reference to Russian figure skater Yulia Lipnitskaya, Shenderovich said he liked her "very much! But if you only knew how much Berliners in the summer of 1936 liked shot putter Hans Woelke ... a smiling, handsome young man who symbolized the youth of the new Germany!"